Fuel oil additive and fuel oil additive composition

ABSTRACT

A fuel oil composition comprises fuel oil and 0.1 to 50,000 ppm of an additive compound having the formula (I) in which R is a hydrocarbyl radical having 10 to 50 carbon atoms, A is an alkylene group having 2 to 6 carbon atoms, m is an integer of 10 to 50 and n is an integer of 1 to 3. It is improved in cleaning property.

FIELD OF THE INVENTION

The present invention relates to a fuel oil additive, particularlygasoline additive and a fuel oil additive composition containing thesame. More particularly, the present invention relates to a fuel oiladditive which exhibits excellent cleaning properties for a fuel intakeunit and a combustion chamber, and a fuel oil additive compositioncontaining the same.

PRIOR ART

The formation of sediment such as sludge or deposit in a fuel system ora combustion chamber of an internal combustion engine exerts an adverseeffect on the function of an engine or exhaust gas.

Therefore, a fuel detergent, particularly a gasoline detergent is addedto gasoline for the purpose of removing the deposit formed in a gasolineintake unit such as a carburetor or an intake valve, inhibiting theformation of deposits and cleaning the combustion chamber. The depositformed in an intake valve or an intake port is causative of lowering inthe power output of an engine, impairment of driving properties orincrease in the amount of exhaust gas. Recently, the performance of anengine has been enhanced more and more to make an engine more sensitiveto the deposit described above. Particularly, the deposit formed in anintake valve has recently become a significant problem. For example, inJapan, the ratio of passenger cars fitted with an electronicallycontrolled fuel injector has increased. An electronically controlledfuel injector can precisely control the mixing ratio of gasoline to airto be effective not only in enhancing the performance of an engine butalso in improving fuel cost and exhaust gas. When deposit is formed inan intake valve, however, the gasoline injected from the injector hitsagainst the deposit to deteriorate its control, so that the drivingproperties are adversely affected.

Various fuel oil additives have been proposed to solve the aboveproblems.

For example, polyetheramines are disclosed in Japanese PatentPublication Nos. 48556/1981, 39278/ 1980 and 33016/1986 and JapanesePatent Laid-Open No. 25489/1980. These polyetheramines are insufficientrespect to the cleaning properties for an intake valve.

Under these circumstances, the present invention aims at providing afuel oil additive which exhibits excellent cleaning properties for anintake valve and is excellent in thermal decomposability and which canbe easily prepared, and a fuel oil additive composition containing thesame.

SUMMARY OF THE INVENTION

The inventors of the present invention have intensively studied to solvethe problems of the prior art and have accomplished the presentinvention.

Namely, the present invention provides a fuel oil additive characterizedby containing a compound represented by the following general formula(1) and a fuel oil additive composition characterized by comprising suchan additive and a mineral or synthetic oil:

    R--O--(AO).sub.m --(C.sub.3 H.sub.6 NH).sub.n H            (1)

wherein R is a hydrocarbyl radical having 10 to 50 carbon atoms; A is analkylene group having 2 to 6 carbon atoms; m is an integer of 10 to 50;and n is an integer of 1 to 3.

The invention provides a fuel oil composition comprising fuel oil and0.1 to 50,000 ppm of an additive compound having the formula (I) inwhich R is a hydrocarbyl radical having 10 to 50 carbon atoms, A is analkylene group having 2 to 6 carbon atoms, m is an integer of 10 to 50and n is an integer of 1 to 3.

    R--O--(AO).sub.m --(C.sub.3 H.sub.6 NH).sub.n H            (I)

It is preferable that the composition comprises 1 to 20,000 ppm of theadditive compound. It may further comprise 0.05 to 20 parts by weight,per 1 part of the additive compound, of a mineral or synthetic oil.

It is preferable that the mineral oil or synthetic oil is selected fromthe group consisting of poly-alpha-olefin, polybutene, an adduct of analcohol with an alkylene oxide, an adduct of an alkylphenol with analkylene oxide, an alkylene oxide polymer such as an addition product ofpropylene oxide or butylene oxide and an ester thereof.

The invention provides an additive composition to a fuel oil comprisingthe additive compound as defined above and a mineral or synthetic oil.It provides a fuel oil additive comprising the above defined compound(I).

The compound represented by the general formula (1) can be prepared bycyanoethylating an adduct of an alcohol, or alkylphenol having 10 to 50carbon atoms and an alkylene oxide with acrylonitrile and hydrogenatingthe obtained product, if necessary, followed by the repetition of thecyanoethylation and the hydrogenation. The cyanoethylation is conductedby stirring the reaction system under heating in the presence of astrong base catalyst such as caustic alkali. The hydrogenation can beconducted in the presence of a hydrogenation catalyst such as Raneynickel.

However, the process for the preparation of the compound represented bythe general formula (1) is not limited to the above process.

When the compound represented by the general formula (1) is prepared bythe above process, the alcohol ROH [wherein R is the same as thatdefined for the general formula (1)]to be used as a raw material musthave 10 to 50 carbon atoms. Examples of the alcohol include varioussaturated and unsaturated natural alcohols; straight-chain monohydricalcohols prepared by the Ziegler process and branched alcohols preparedby the oxo process or the Guerbet reaction.

Preferable examples of the alcohol include natural alcohols such asdecyl, lauryl, palmityl, stearyl, eicosyl, behenyl, oleyl, elaidyl anderucyl alcohols; straight-chain monohydric alcohols having 10 to 30carbon atoms prepared by the Ziegler process; branched alcohols having10 to 24 carbon atoms prepared by the oxo process; and branched alcoholshaving 16 to 24 carbon atoms prepared by the Guerbet reaction.

The alkylphenol to be used as a raw material is one having one or twoalkyl groups each having 4 to 40 carbon atoms, preferably 4 to 30 carbonatoms to contain 10 to 50 carbon atoms in total.

Particular examples thereof include butylphenol, amylphenol,octylphenol, nonylphenol, dinonylphenol, dodecylphenol, cumylphenol,alkylphenols wherein said alkyl group has 18 to 24 carbon atoms, andalkylphenols prepared by the reaction of an α-olefin having 6 to 30carbon atoms with phenol.

The alkylene oxide to be added to the above alcohol or alkylphenol musthave 2 to 6 carbon atoms. Propylene oxide and butylene oxides (1,2-,2,3-, 1,3-and 1,4-isomers and mixtures thereof) are particularlypreferable. The number of the alkylene oxide molecules to be added mustbe at least 10. When this number is less than 10, the resulting additivewill be poor in the cleaning properties for an intake valve, thus beingunfit for the purpose of the present invention. When it exceeds 50, onthe contrary, the preparation of such an adduct will be difficult, thusbeing uneconomical, though the number has not particularly an upperlimit.

The adduct of an alcohol as described above with an alkylene oxide asdescribed above can be prepared by various processes. For example, agaseous or liquid alkylene oxide having 2 to 6 carbon atoms (such asethylene oxide or propylene oxide) is added to an alcohol in thepresence of a catalyst such as caustic alkali under heating, ifnecessary in the presence of also a proper solvent.

Two or more alkylene oxides may be additionpolymerized in block or atrandom.

In the above general formula (1), n is an integer of 1 to 3. When n is 4or above, emulsification will occur disadvantageously when water isincluded in a fuel oil.

The additive of the present invention is further improved in the depositremoving effect and the cleanness retaining effect, when usedsimultaneously with a mineral or synthetic oil generally called the"carrier oil"., Particularly, the simultaneous use of a synthetic oil ismore effective. Examples of such a synthetic oil include olefin polymerssuch as poly-αolefin and polybutene; adducts of alcohol or alkylphenolwith alkylene oxide; and alkylene oxide polymers such as additionproducts of alkylene oxide such as propylene oxide or butylene oxide andesters or ethers of the products. The amount of the mineral or syntheticoil to be added is preferably 0.05 to 20 parts by weight per one part byweight of the compound represented by the above general formula (1).

The additive for fuel oils according to the present invention exhibitsexcellent cleaning properties for a fuel intake unit and a combustionchamber, particularly for an intake valve. Further, it exhibits anexcellent cleanness retaining effect even when used in a small amount.

The fuel oil additive according to the present invention is added to afuel oil so as to give a concentration of 0.1 to 50,000 ppm. Althoughthe addition of a larger amount of the additive gives more excellentcleaning properties, a practically sufficient effect can be obtained ata concentration of 1 to 20,000 ppm.

The additive of the present invention may be used together with otherfuel oil additives such as rust preventive, anti-emulsion agent,antioxidant or metal deactivator. As described above, a fuel oiladditive composition excellent in cleaning properties can be obtained bythe addition of the fuel oil additive according to the presentinvention.

EXAMPLE

The present invention will now be described in more detail by referringto the following Synthesis Examples and Examples, though the presentinvention is not limited by them.

SYNTHESIS EXAMPLE 1

0.40 mol of nonylphenol (BO)20 (adduct of nonylphenol with twenty1,2-butylene oxide molecules) was put in a 1-(four-necked flask. Whilekeeping the contents at 76 to 80° C by heating and stirring in thepresence of 2 mmol of caustic potash as a catalyst, 0.48 mol ofacrylonitrile was dropped into the flask in a nitrogen atmosphere over aperiod of 3 hours and the resulting mixture was further reacted for 2hours. The caustic potash was neutralized with acetic acid and excessacrylonitrile was distilled away in a vacuum. Thus, a cyanoethylatedderivative was obtained.

300 g of the cyanoethylated derivative was put in a 1-l autoclave andhydrogenated under a hydrogen pressure of 20 kg/cm² in the presence ofRaney nickel catalyst to give a compound represented by the formula:##STR1##

SYNTHESIS EXAMPLE 2

In a similar manner to that of Synthesis Example 1, a compoundrepresented by the formula: ##STR2## was prepared from dodecylphenol(BO)16 (adduct of dodecylphenol with sixteen 1,2-butylene oxidemolecules).

SYNTHESIS EXAMPLE 3

In a similar manner to that of Synthesis Example 1, a compoundrepresented by the formula: ##STR3## was prepared from dinonylphenol(BO)₁₅ (PO)₁₀ (adduct of dinonylphenol with fifteen 1,2-butylene oxidemolecules and ten propylene oxide molecules).

SYNTHESIS EXAMPLE 4

In a similar manner to that of Synthesis Example 1, a compoundrepresented by the formula: ##STR4## was prepared from 2-heptylundecanol(BO)30 (adduct of 2-heptylundecanol with thirty 1,3-butylene oxidemolecules).

SYNTHESIS EXAMPLE 5

The compound represented by the formula: ##STR5## prepared in SynthesisExample 1 was cyanoethylated in a similar manner to that of SynthesisExample 1 and thereafter hydrogenated to give a compound represented bythe formula: ##STR6##

SYNTHESIS EXAMPLE 6

In a similar manner to that of Synthesis Example 1, a compoundrepresented by the formula:

CH₃ (CH₂)₇ CH=CH(CH₂)₇ CH₂ O(BO)₂₀ CH₂ CH₂ CH₂ NH₂

was prepared from oleyl alcohol (BO)₂₀ (adduct of oleyl alcohol withtwenty 1,2-butylene oxide molecules)

SYNTHESIS EXAMPLE 7

In a similar manner to that of Synthesis Example 1, a compoundrepresented by the formula:

    CH.sub.3 (CH.sub.2).sub.14 CH.sub.2 O(BO).sub.15 CH.sub.2 CH.sub.2 CH.sub.2 NH.sub.2

was prepared from palmityl alcohol (BO)₁₅ (adduct of palmityl alcoholwith fifteen 1,2-butylene oxide molecules).

EXAMPLE 1

The additives of the present invention prepared in the foregoingSynthesis Examples 1 to 7 and a reaction product of ethylenediamine witha chloroformate of dodecylphenol (BO)₂₅ (adduct of dodecylphenol withtwenty-five 1,2-butylene oxide molecules) [hereinafter abbreviated, as"comparative additive"] were each subjected to the following thermaldecomposition test to determine whether the additive in itself formsdeposit in a combustion chamber or not.

Namely, about 1 g of an additive sample (50% kerosine solution) wasaccurately weighed into

an aluminum cup. The cup was placed in a thermostatic chamber and keptat 200° C. for 15 hours to determine the residual weight. The percentagedecomposition was calculated according to the following equation whereinWi is the weight of the sample used and Wr is the residual weight:

    Rate of decomposition (%) = (Wi-Wr-Wi/2) / (Wi/2) × 100

Further, the appearance of the residue was observed with the naked eye.

The results are given in Table 1.

                  TABLE 1                                                         ______________________________________                                                       Rate of                                                               Kind of decomposition                                                                              Appearance of                                            additive                                                                              (%)          residue                                           ______________________________________                                        Invention                                                                              Syn. Ex. 1                                                                              92           light lacquer-like                                     Syn. Ex. 2                                                                              91           "                                                      Syn. Ex. 3                                                                              90           "                                                      Syn. Ex. 4                                                                              95           "                                                      Syn. Ex. 5                                                                              85           "                                                      Syn. Ex. 6                                                                              81           "                                                      Syn. Ex. 7                                                                              85           "                                             Comparative        70           lacquer-like                                  ______________________________________                                    

As is apparent from the results given in Table 1, all of the additivesof the present invention exhibited excellent thermal decomposability.

EXAMPLE 2 (fleet test)

One tank (61 l) of gasoline containing 1% by weight of an additive wasused in the travelling on a common road. Before and after the test, theengine was disassembled to observe the intake unit (intake valve andintake port), combustion chamber and carburetor and intake valve. Thus,the extent of the removal of deposit was evaluated. The car used isTOYOTA CARINA 1800 cc (engine type: 1S). This car was one which had runfor about 20000 km.

The extent of the removal of deposit was evaluated according to thefollowing criteria:

    ______________________________________                                               X          increase in the amount of deposit                                  --         no change                                                          Δ    poor deposit removing effect                                       ◯                                                                            tolerable deposit removing effect                                  ⊚                                                                         excellent deposit removing effect                           ______________________________________                                    

The results are given in Table 2.

                  TABLE 2                                                         ______________________________________                                                 Extent of the removal of deposit                                     Fuel                       upper                                              oil                        part of                                            addi-      intake  intake  combustion                                                                            piston                                                                              carbu-                               tive *1    valve   port    chamber head  retor                                ______________________________________                                        Inven-                                                                              50% so-  ∘˜⊚                                                  ∘                                                                       ∘                                                                         Δ                                                                             ∘                      tion  lution of                                                                     the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 1                                                                         50% so-  ∘˜⊚                                                  ∘                                                                       ∘˜Δ                                                           Δ                                                                             ∘                            lution of                                                                     the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 2                                                                         50% so-  ∘˜⊚                                                  ∘                                                                       Δ Δ                                                                             ∘                            lution of                                                                     the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 3                                                                         50% so-  ∘˜⊚                                                  ∘                                                                       Δ Δ                                                                             ∘                            lution of                                                                     the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 4                                                                         50% so-  ∘˜⊚                                                  ∘                                                                       ∘˜Δ                                                           Δ                                                                             ∘                            lution of                                                                     the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 5                                                                         50% so-  ∘                                                                         ∘                                                                       Δ ∘˜Δ                                                         ⊚                         lution of                                                                     the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 6                                                                         composi- ⊚                                                                      ∘                                                                       ∘˜Δ                                                           ∘˜Δ                                                         ∘                            tion con-                                                                     taining                                                                       the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 1                                                                         composi- ⊚                                                                      ∘                                                                       ∘˜Δ                                                           ∘˜Δ                                                         ∘                            tion con-                                                                     taining                                                                       the addi-                                                                     tive of                                                                       Syn.                                                                          Ex. 3                                                                   50% solution of                                                                          ∘˜Δ                                                           ∘˜Δ                                                           --      --    Δ                              the comparative                                                               additive                                                                      ______________________________________                                        Note                                                                          *1 each of the 50% solutions was prepared by diluting each of the             additives prepared in Synthetic Examples and Comparative one                  with an aromatic solvent to 50%. The compositions each comprise               the following components:                                                         compound prepared in Synthesis Example                                                                1 part by weight                                      adduct of nonylphenol with 15                                                                         1 part by weight                                      butylene oxide molecules                                                      [nonylphenol (BO).sub.15 ]                                                    aromatic solvent        2 part by weight                              

EXAMPLE 3 (fleet test 2)

The fuel oil additives were examined for the cleanness retaining effectaccording to the following test.

Regular gasoline containing 250 ppm of a fuel oil additive was used inthe travelling on a common road. Before and after the test, the enginewas disassembled to observe the intake unit (intake valve, intake portand carburetor) and combustion chamber. Thus, the extent of theformation of deposit was evaluated. With respect to the intake valve,the weight thereof was measured before and after the test to determinethe amount of the deposit formed. The car used is NISSAN CEDRICBrougham) VIP 3000 cc (engine type: VG-30G).

Prior to the test, the intake unit and combustion chamber of the carwere cleaned to remove the deposit.

The extent of the retention of cleanness was evaluated according to thefollowing criteria based on the result given when no fuel oil additivewas used.

    ______________________________________                                              X         increase in the amount of deposit                                   --        equivalent to the result given when no                                        additive was used                                                   Δ   the cleanness retaining effect is a little                                    superior to the one exhibited when no                                         additive was used                                                   ◯                                                                           nearly no deposit was formed                                        ⊚                                                                        no deposit was formed                                         ______________________________________                                    

The results are given in Table 3.

                                      TABLE 3                                     __________________________________________________________________________                 Extent of the retention of cleanness                                                  upper part of  wt. change of                             Fuel oil     intake                                                                            intake                                                                            combustion                                                                           piston                                                                            carbu-                                                                            intake                                    additive *1  valve                                                                             port                                                                              chamber                                                                              head                                                                              retor                                                                             valve *2 (mg)                             __________________________________________________________________________    Invention                                                                          50% solution of                                                                       ∘                                                                     ∘                                                                     Δ                                                                              --  ∘                                                                     58                                             the additive of                                                               Syn. Ex. 1                                                                    50% solution of                                                                       ∘                                                                     ∘                                                                     Δ                                                                              --  ∘                                                                     70                                             the additive of                                                               Syn. Ex. 2                                                                    50% solution of                                                                       ∘                                                                     ∘                                                                     Δ                                                                              --  ∘                                                                     72                                             the additive of                                                               Syn. Ex. 3                                                                    50% solution of                                                                       ∘                                                                     ∘                                                                     Δ                                                                              --  ∘                                                                     65                                             the additive of                                                               Syn. Ex. 4                                                                    50% solution of                                                                       ∘                                                                     ∘˜⊚                                              Δ                                                                              --  ⊚                                                                  85                                             the additive of                                                               Syn. Ex. 5                                                                    composition                                                                           ∘˜⊚                                              ∘˜⊚                                              Δ˜∘                                                          Δ                                                                           ∘                                                                     21                                             containing the                                                                additive of                                                                   Syn. Ex. 1                                                                    composition                                                                           ∘˜⊚                                              ∘˜⊚                                              Δ˜∘                                                          Δ                                                                           ∘                                                                     29                                             containing the                                                                additive of                                                                   Syn. Ex. 3                                                               50% solution of the                                                                        Δ                                                                           Δ                                                                           --     --  ∘                                                                     120                                       comparative additive                                                          __________________________________________________________________________    Note                                                                          *1 each of the 50% solutions was prepared by diluting each of the             additives prepared in                                                         Synthetic Examples and Comprative one with an aromatic solvent to 50%.        The compo-                                                                    sitions each comprise the following components:                                 compound prepared in Syn. Ex.                                                                 1 part by weight                                              adduct of nonylphenol with 15                                                                 1 part by weight                                              butylene oxide molecules                                                      [nonylphenol (BO).sub.15 ]                                                    aromatic solvent                                                                              2 parts by weight                                           *2 The weight change of an intake valve is given by an average of the         weight changes                                                                of six intake valves and corresponds to the amount of the deposit             formed.                                                                   

EFFECT OF THE INVENTION

The fuel oil additives according to the present invention are superiorto the comparative additives in thermal decomposability and has beenascertained from the results of fleet tests to be excellent in thedeposit removing power and cleanness retaining power for a fuel intakeunit and a combustion chamber.

We claim:
 1. A fuel oil composition which comprises(a) fuel oil; (b) 1to 20,000 ppm of an additive compound having the formula

    R--O--(AO).sub.m --(C.sub.3 H.sub.6 NH).sub.n H            (I)

wherein R is a hydrocarbyl radical having 10 to 50 carbon atoms, A is analkylene group having 2 to 6 carbon atoms, m is an integer of 10 to 50and n is an integer of 1 to 3; and (c) 0.05 to 20 parts by weight, per 1part of said additive compound, of a mineral or synthetic oil.
 2. Thecomposition as claimed in claim 1 in which the mineral oil or syntheticoil is selected from the group consisting of poly-alpha-olefin,polybutene, an adduct of an alcohol with an alkylene oxide, an adduct ofan alkylphenol with an alkylene oxide, an alkylene oxide polymer andester thereof.
 3. The composition as claimed in claim 1 in which themineral oil or synthetic oil is selected from the group consisting of anaddition product of propylene oxide or butylene oxide and an esterthereof.
 4. A fuel additive composition which comprises an additivecompound having the formula

    R--O--(AO).sub.m --(C.sub.3 H.sub.6 N).sub.n H

wherein R is a hydrocarbyl radical having 10 to 50 carbon atoms, A is analkylene group having 2 to 6 carbon atoms, m is an integer of 10 to 50and n is an integer of 1 to 3; and 0.05 to 20 parts by weight, per 1part of said additive compound, or a mineral or synthetic oil.
 5. Thecomposition as claimed in claim 4 wherein the mineral oil or syntheticoil is selected from the group consisting of poly-alpha-olefin,polybutene, an adduct of an alcohol with an alkylene oxide, an adduct ofan alkylphenol with an alkylene oxide, an alkylene oxide polymer and anester thereof.
 6. The composition as claimed in claim 4 wherein themineral oil or synthetic oil is selected from the group consisting of anaddition product of propylene oxide or butylene oxide and an esterthereof.